Preheat your oven to 400°F (200°C).
Wash the sweet potato and cut it into 1-inch cubes.
Trim the tough, woody ends off the asparagus spears.
In a small bowl, whisk together the olive oil, lemon juice, minced garlic, rosemary, thyme, sea salt, and black pepper.
Place the chicken breast, sweet potato cubes, and asparagus spears onto a large parchment-lined sheet pan.
Drizzle the lemon-herb oil over the chicken and vegetables, tossing the produce and coating the chicken thoroughly to ensure maximum flavor.
Roast in the oven for 20 to 25 minutes until the chicken reaches an internal temperature of 165°F and the sweet potatoes are fork-tender.
Allow the chicken to rest for 5 minutes before slicing to keep it juicy, then serve alongside the roasted vegetables.